Chinese President Xi Jinping was on hand in the eastern city of Nanjing on Wednesday to mark the 80th anniversary of a wartime massacre by Japanese troops, but commemorations were low key in an apparent gesture to Tokyo.

In a rare move, Xi attended the event but did not make a speech – a sharp contrast to three years ago when the president addressed the crowd.

The host at Wednesday’s event was also lower ranking than his counterpart in 2014, when China made the anniversary a national day of remembrance.

China says about 300,000 civilians and soldiers were killed in a frenzy of murder, torture, rape, arson and looting in the six weeks after the invading Japanese military entered Nanjing, then the Chinese capital, on December 13, 1937.

Japan’s Jiji news agency said it was rare for Xi to attend a national event without speaking publicly but the move could be a signal to Japan of improving ties between the two countries.

Chinese international relations analysts said Xi’s presence lent weight to the occasion but both sides were working to improve Sino-Japanese relations.

“China does not play history as a card,” Jiang Yuechun, a Japanese affairs specialist at the China Institute of International Studies, said. “But it is true that the China-Japan relationship is at an important turning point, and we see efforts from both sides.”

Officials from both countries are discussing possible state visits by Xi and Japanese Prime Minister Shinzo Abe as part of a push to improve ties but observers say there are still many barriers, including Japan’s wartime past, in the way.

Liu Junhong, a Japanese specialist at the China Institute of Contemporary International Relations, said good faith and mutual trust were two preconditions for the visits.

The anniversary of the 1937 massacre remains one of the most fraught issues for the two powerful neighbours, who dispute the toll. Some Japanese archconservatives also deny the episode took place at all.

On Wednesday, Yu Zhengsheng, chairman of the Chinese People’s Political Consultative Conference, told the Nanjing gathering that China was on a stronger economic, scientific and military footing than it was in the 1930s and 1940s, but would always work for world peace and defend the international order.

“China will always adhere to the path of peaceful development. However developed we may become, China will never seek hegemony and never go in for expansion and never impose our tragic experiences on other nations,” Yu said.

He also referred to Japanese wartime atrocities in other countries, including the 1942 Bataan Death March and the Thai-Burma railway, adding that memories of the war should be retained to ensure peace.

Yu said China and Japan should “learn from history and face the future, continue to be friends for generations, and jointly contribute to world peace”.

“China will … deepen its relationships with neighbouring countries, including Japan,” Yu said.